Mometrix NLN Science Portion

volumetric flask

prepares a specific volume of a solution

erlenmeyer flasks

used for mixing, transporting, and reacting but are not appropriate for providing exact measurements

pipette

used to measure small solution which can be found on the meniscus

repipette

dispenses solution

beakers

measures mass or dissolve a solvent into a solute

does not measure volume as accurately as a volumetric flask, pipette, graduated cylinder, or burette

burette

dispenses liquid and is similar to a graduated cylinder

what type of microscope is commonly used in most labs

optical or light microscopes

digital microscopes

use a camera to view sample

scanning electron microscope

provides greater surface topography and better magnification than optical microscopes

please place the 3 types of balances from most accurate to least

1. electronic balance

2. triple beam balance

3. spring balance

chromatography

set of laboratory techniques used to separate and analyze mixtures

Preparative chromatography

purifying substance for further use rather than further analysis

gas chromatography

the separation of substance in gas form

reagent or reactant

used for chemical reactions

Electrophoresis

seperation of molecules based on electrical change

calorimetry

determine the amount of heat released or absorbed in a chemical reaction

titrtaion

determines the precise end point of a reaction

scientific theory

proposition explaining why or how something happens and is built on scientific laws

these theories ca be tested but not proven

hypothesis

an educated guess that is not yet proven

predicts an outcome of an experiment

the steps of the scientific method

1. identify the problem or pose a question

2. formulate a hypothesis or an educate guess'

3. conduct an experiement

4. observe the results of the test

5. draw conclusions

Deka

10 ^1

Hecto

10²

Kilo

10³

Mega

10^6

Giga

10^9

Terra

10^12

Deci

10^-1

Centi

10^-2

Mili

10^-3

Micro

10^-6

Nano

10^-9

Pico

10^-12

Ampre

measures electric current

kelvin

measures thermodynamic temp

candela

measure luminous intensity

mole

used to measure the amount of substance a5t a molecular level

Meter

measure length

kilogram

measure mass

significant figures or digits

used to determine the accuracy of measurement or level of confidence one has in measurement

independent variable

being manipulated for an experiment

horizontal axis (X axis)

dependent variables

may change based off of independent variable

y axis vertical axis

Random errors

result in collected data that is wildly diff from the rest of the data

systemic errors

this can indicate a bias

will show up consistently throughout the data resulting in a flaw of design

what makes a positive exponent in scientific notation

if the number is greater than or equal to 1 and less than 10

but if this is not the case it is a negative exponent

which way is the decimal moved for a positive exponent

to the right

and left for negative

standard deviation

how far a point is most likely to be from the mean

prokaryotes

domains of bacteria and archea

much smaller than eukaroyotes

1 to 2 micrometers in diameter

unicellular

large surface to volume ratio creating a high matabolic rate

Eukaryotes

10 to 100 micrometers in diameter

smaller area to volume and lower metabolic rate

where is the DNA of Prokaryotes located

located in the center of the call called the nucleoid

dies not contain a nucleus due to its small size

Membrane Bound Organelles in Eukaryotes

independent of cell membrane

contains nucleus

much higher intracellular division

Peptidoglycan

large polymer of amino acids and sugars

helps maintain strength in cell walls

fungi cell walls contain

chitin

do animal cells have a cell wall

no

where are chromosomes located in a prokaryote

nucleoid

how do prokaryotes reproduce

binary fission

how do eukaryotes reproduce

mitosis

where is the DNA in eukaryotes located

in membrane bound nucleus

autrophs

plants that produce their own food

heterotrophs

cannot produce own food so animal cells must look for own food

cell membrane/plasma membrane

thin semipermeable membrane of lipids and proteins

phospholipid bilayer or double layer

hydrophilic (water-loving) ends facing the external environment

hydrophobic (water-fearing) face the inside of the membrane

purpose of cholesterol in the cell

adds stiffness and flexibility

glycolipids

help the cell recognize other cells of organisms

nuclear envelope

double layered membrane with the outer layer connected to the endoplasmic reticulum

purpose of nucleous

assembles ribosomes with the help of ribosomal RNA and proteins

functions of the nucleus

genetic material, production of ribosomes, and transcription of RNA

chloroplasts

large organelles that are enclosed in double membrane

thylakoids

discs arranged in stacks called grana

have chlorphyll molecules on their surfaces

stromal lamelle

seperate thylakoid stacks

Stroma

sugars are formed in the stroma (inner portion of the chloraplasts)

light reaction of photosynthesis in the grana and the dark reaction occurs in the stroma

chloraplasts

preform photosynthesis

food in the form of sugar for plants

have their own DNA and can reproduce by fission independently

synthesize and store startch

Plastids

found in plants and algae that use to synthesize and store food

Amyloplasts

store starch formed from long chains of glucose produced during photosynthesis

convert granules back to sugar

fruits and potato tubers have larger numbers of amyloplasts

mitochondria purpose

maintains calcium concentrations, forms blood components and hormones, and is involved in activating cell death pathways

mRNA

used for ribosome to generate a specific protein sequence

tRNA

collects the amino acids and delivers them to ribosomes

Microtubles and Microfilaments

help transport materials throughout the cell and are major components in cilia and flagella

3 stages of the cell cycle

1. interphase

2. mitosis

3. cytokinesis

interphase

longest stage (cells spend 90% of its life in interphase)

cell grows and copies its DNA

consists of two growth periods G1 and G2

gap 1 → synthesis → gap 2

G1 Phase

cell increases number of organelles by forming diploid cells

S phase

DNA is replicated and chromosomes double

G2 Phase

cell synthesizes needed proteins and organelles, continues to increase in size, and mitosis can begin once this phase ends

Mitosis

one parent cell divides into two identical daughter cells

what are the 4 phases of mitosis in order and what does each one do?

1. Prophase: spindle fibers appear and the DNA is packaged as visible chromosomes. the nuclear membrane also breaks down and the nucelous disappears.

2. Metaphase: the spindle apparatus is formed and the centromeres of the chromosome line up on the equilateral plane

3. Anaphase: centromeres divide and two chromitads seperate while they are pulled to opposite ends of the cell

4. telophase: spindle fibers disappear, the nuclear membrane reforms, and the DNA in the chromatids is decondensed

Cytokinesis

dividing of the cytoplasm and cell membrane through the pinching of the cell into new daughter cells at the end of mitosis

this occurs at the end of telophase when actin filaments forms a narrow ring that narrows and divides the cell

Meiosis

cell division where the number of chromesomes is reduced by half which produces gametes, eggs, and sperm

occurs in two stages

meiosis I

cell replicates its DNA in interphase and then continues through prophase I, metaphase I, anaphase I, and telophase I

at the end of this stage, there will be two daughter cells that have the same number of chromosomes from the parent cells

Meiosis II

cells enter brief interphase but does not replicate its DNA

gos through prophase II, Metaphase II, Anaphase II, Telophase II

the unduplicated chromosomes split and at the end of telophase II there are 4 daughter cells that have half the number of chromosomes as the parent cell

First checkpoint

end of G1

this is where a cell might continue with division, be delayed, or rest

Resting phase in Animals is what

G0/Restriction

Second checkpoint

just before the end of G2 phase and just before the cell enters prophase

third checkpoint

occurs at metaphase to check that chromosomes are lined up along the equalilateral plane

Point mutations

changes in a single nucleotide in a DNA sequence

Missense mutations

result in codon for a different amino acid

silent mutation

result in codon for the same amino acid as original sequence

nonsense mutation

insert premature stop codon, resulting in non functional protein

frameshift mutation

changes the reading from of mRNA, resulting in formation of new protein product

inversion

when a piece of chromosome inverts or flips over

somatic mutation

develop after conception and occur in an organism’s body cells such as bone cells, liver cells, or brain cells

cannot be passed from parent to offspring

may cause cancer or other diseases

germline mutation

present at conception and occur in germ cells (egg or sperm)

inherited